All Creatures Great and Small says goodbye (for now) to two long-running characters

The theme of All Creatures Great and Small season 6 has undoubtedly been transition.

From adjusting to life in the aftermath of the war – which has been particularly challenging for Tristan – to a Skeldale House in turmoil following Mrs Hall's multi-year absence, from Helen and James becoming parents for the second time to embracing game-changing veterinary advancements, all of the characters have been forced to stay nimble over the past few years.

And now, Jenny Alderson is officially flying the nest – an especially emotional development for her dad Richard and for Helen, who essentially became her surrogate mum after theirs died.

In the latest episode, Jenny received the letter she’d been waiting for: a place at nursing college in London – news met with elation by Helen, who gave her a big hug while their dad looked on.

Of course, Richard was proud of his daughter, but he was also worried about his youngest heading off into the world for the first time – and to the Big Smoke, of all places.

His panic then rose further when he learned that Jenny's registration date was in just three weeks' time. But again, Helen remained positive and level-headed as she set about making a list to ensure Jenny would have everything she needed.

That composure didn't last long, though. Helen's demeanour soon shifted when she was confronted with the possibility that Jenny might not return to Yorkshire after completing her time at college, instead choosing to stay in London or move elsewhere. And before long, doubts crept in, with Helen arriving at the conclusion that her sister wasn't at all prepared.

"She's not ready, not one bit of it," she confided in James, a solemn expression splashed across her face.

But after another conversation with her husband – in which he made the very astute point that no one can ever be truly ready to leave home, but that it can lead to the greatest adventure of one's life – Helen gradually came around to the idea.

And after watching a very impressive display from Jenny with the horses, it was soon Helen convincing her sister, who had started to fret herself, that she had to take this opportunity.

"I don't know anything about London, I don't know where anything is, I don't know anyone," she said.

"Well, that's what adventures are for, isn't it? Discovering all them things," replied Helen.

Speaking ahead of the season premiere, Rachel Shenton described Helen and Jenny's arc in the show's sixth chapter as "another wave of change".

"We've seen the signs – Jenny wondering what else is out there, talking about cities and new experiences," she added.

"With Doris arriving last season, her head was turned a bit, and she started thinking about what else is out there. So Helen's always quietly known that moment might come.

"But I don't think she copes as well as she thought she would. It makes Helen look at her own life – the things she didn't do, the opportunities she maybe didn't have.

"That time's passed for her now, with two children. So it's a bittersweet moment, but also a lovely evolution in their relationship."

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And in a lovely turn of events, Helen will also get to enjoy a new experience of her own when accompanying Jenny to London to help her settle in – a Richard Alderson suggestion.

After initially thinking she couldn't, Helen agreed to join her sister for a few weeks, following some gentle encouragement from James, who must now step up in his wife's absence.

"There was definitely a little Rachel-shaped hole on set during this series," said Nicholas Ralph of working without Shenton, who had gone on maternity leave.

"We all really missed her – but of course, she had far more important things going on than we did

"And it was the same for James, really. Helen is his other half, his missing piece. She supports him, guides him, pushes him when he needs it. She's a real rock for James, just as he is for her.

"So that separation was felt both onscreen and off. James really feels it, and we, as a company of actors, felt it too. We missed her hugely."

All Creatures Great and Small season 6 airs on Thursdays on 5. You can order James Herriot's All Creatures Great and Small from Amazon.

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